package everyday.luogu;

import java.util.HashSet;
import java.util.Scanner;

/**
 * @Author: wenjingyuan
 * @Date: 2022/11/19/15:46
 * @Description:
 */
public class Num1 {
    public static void main(String[] args){
        Scanner scanner=new Scanner(System.in);
        HashSet<String> set=new HashSet<>();
        while(true){
            String next=scanner.next();
            set.add(next);
            if (next == "0")
            break;
        }
        for(String s:set){
            System.out.println(s);
        }
    }
}
